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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #1 (Edited)
Over the course of the last 3 years involved with the 107 community, the one thing that seems to elude the membership is a definitive source for vacuum troubleshooting.
There are many variables through the lengthy 107 manufacturing run and yet no one manual offers a vacuum diagram for all of the various systems. It is only through the kindness of other 107 owners that vacuum problems seem to be resolved.
With that being said, why not try to pool our vacuum resources into one thread.
Each post titled with the appropriate section followed by a scanned, hand drawn or pdf drawing or photos. Links to vacuum systems would be great too.
Some attachments might get posted more than once due to the multiple models it covers.
I think the key would be in the title of the post so that anyone doing a search would, hopefully, get a hit.


**************NOTE / EDIT*************

This thread can be edited if incorrect info is posted. Please let me know.
 

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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #5
Oh moderators !!!. This needs to move up to stickville.
It needs to get it's legs underneath it first. Let's see how many play. I can't help here at home because I don't have a scanner and my PC hates my CD manual. I'll try from work.
 

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Premium Member
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9,894 Posts
71 to 73 350 450 SL 107 vacuum systems

It needs to get it's legs underneath it first. Let's see how many play. I can't help here at home because I don't have a scanner and my PC hates my CD manual. I'll try from work.
I posted the diagrams for the early 107 engine, door locks and heating system in the other thread. Question - Is there a way to upload the pictures to benzworld - my web space is getting kind of full!

Here they are again. Maybe someone with a manual could add the later models. I am trying to get ready for a trip South!

It's now 2017! Sorry, the links are dead because Cogeco destroyed my pics :(

Engine vacuum retard:


Heater Vacuum controls:




Door Lock vacuum systems (several models)


 

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Premium Member
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6,077 Posts
OK, so this is the vacuum diagram to a 1978-1980 450SL with the K-Jet system. Click the picture to see it full size.

View attachment 177276

In case you can't read the legend:

1) Mixture Regulator Assembly - controls the fuel mixture
2) Distributor - duh
3) Switch over valve - this changes the timing of the engine based on whether the AC compressor is running or not.
4) EGR Valve - part of the emissions controls.
5) Check Valve - this keeps vacuum going one way. These fail and cause all kind of wierdness. Easy to check with a hand vacuum pump and inexpensive to replace.
6) Charcoal Canister - more of the emissions controls. Soaks up the fuel vapors from the gas tank.
7) AIR pump - more emissions
8) Diverter Valve - yet more emissions
9) Check valve - see 5
10) Thermo vacuum valve (40C/104F) - this stops or allows vacuum to pass through depending on engine temperature
11) Thermo vacuum valve (17C/64F) - see 10
12) Exhaust pressure transducer - and still more emissions. This is a gateway that routes vacuum all over the place.
A) This is only on original California cars - you can tell if yours is original by the color of the emissions sticker on the radiator support. Yellow means your car is an original California car. Black means it's a federal (some other state) car.
B) This runs back to the gas tank vent.

After 30 years the original vacuum lines are old, brittle and probably cracked. And, chances are, there was at least one fumble-fingered idiot who worked on this car at some point in the last 30 years. Pick a vacuum circuit and trace it out, from end to end. Make sure the lines are all good and the rubber bits are not old and cracked. CHECK THEM WITH YOUR HAND VACUUM PUMP! Just looking at them won't tell you, because it might look all right and still have a leak. The K-Jet engine is incredibly sensitive to unregulated air, and a vacuum leak definitely qualifies as unregulated air. Vacuum leaks in this engine cause stumbling idle, weak power, bad gas mileage and - worst case scenario - burned valves due to extremely lean running conditions. Making sure the vacuum is in order should probably be your first priority when you get a 107.
 

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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #8
What is this?


EDIT: 1981 380SL
 

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It Is What It Is, Dude
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22,839 Posts
I'm going to stickify this for a while, to see if we can get ShiftNob some more cowbell.

I never did any vacuum work when I had the old SLC, I had it done long before I found this place. So I have no tales to tell here. But I do know from earlier posts there is an all but impossible to reach fitting at the rear of the engine. Who has actually done that repair? Tell us the story.

And any other stories about the resolution of your vacuum issues.
 

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Outstanding Contributor , Bob's Your Uncle!
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29,105 Posts
Discussion Starter #10
One of the first things I did as a new SL father, was to change every vacuum line and fitting that I could see. Quite a job, but easier on an SL with the M110 and no central locking system.



We need more diagrams with official post titles to make the searches easier.
Personally, I'm a computer loser. No scanner and my CD is disliked by my PC.
Lose lose situation.
 

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Outstanding Contributor , Bob's Your Uncle!
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29,105 Posts
Discussion Starter #11
1982 380 SL

Vacuum Diagram.
 

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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #12

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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #13

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Outstanding Contributor , Bob's Your Uncle!
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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #15
Help with this one:
 

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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #16
87 560 SL

Including central locking
 

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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #18

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Outstanding Contributor , Bob's Your Uncle!
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Discussion Starter #19 (Edited)
81 380 SL

Complete!
 

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